Fix behavior when hashValue is duplicated

Sources/Algorithm.swift

@@ -599,8 +599,7 @@ private struct TableKey<T: Hashable>: Hashable {
 
  static func == (lhs: TableKey, rhs: TableKey) -> Bool {
  return lhs.hashValue == rhs.hashValue
- || lhs.pointer.distance(to: rhs.pointer) == 0
- || lhs.pointer.pointee == rhs.pointer.pointee
+ && (lhs.pointer.distance(to: rhs.pointer) == 0 || lhs.pointer.pointee == rhs.pointer.pointee)
  }
 }
 

Tests/AlgorithmTest.swift

@@ -235,6 +235,42 @@ extension AlgorithmTestCase {
  ]
  )
  }
+
+ func testSameHashValue() {
+ struct A: Hashable, Differentiable {
+ let hashValue = 0
+ let actualValue: Int
+
+ init(_ actualValue: Int) {
+ self.actualValue = actualValue
+ }
+
+ func isContentEqual(to source: A) -> Bool {
+ return actualValue == source.actualValue
+ }
+ }
+
+ let section = 0
+
+ let source = [A(0), A(1)]
+ let target = [A(0), A(2)]
+
+ XCTAssertExactDifferences(
+ source: source,
+ target: target,
+ section: section,
+ expected: [
+ Changeset(
+ data: [A(0)],
+ elementDeleted: [ElementPath(element: 1, section: section)]
+ ),
+ Changeset(
+ data: target,
+ elementInserted: [ElementPath(element: 1, section: section)]
+ )
+ ]
+ )
+ }
 }
 
 /// Test algorithm for sectioned collection.